package C;


import java.math.BigInteger;
import java.util.Scanner;

public class C62 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String input = sc.nextLine();

        System.out.println(getResult(input));
    }

    public static String getResult(String input) {
        BigInteger sum = new BigInteger("0");
//        int sum = 0;
        int flag = 1;
        int num;
        StringBuilder sb = new StringBuilder("0");
        for (int i = 0; i < input.length(); i++) {
            char c = input.charAt(i);
            if (Character.isUpperCase(c) || Character.isLowerCase(c)) {
                int x = Integer.parseInt(sb.toString());
                sb.setLength(0);
                sb.append("0");
                sum = sum.subtract(new BigInteger(String.valueOf(x)));
                flag = 1;
                continue;
            }

            if (c == '-') {
                flag = -1;
                continue;
            }
            //下面是数字情况
            if (flag == 1) {
                sum = sum.add(new BigInteger(String.valueOf(c)));
                continue;
            } else  {
                sb.append(c);
            }
        }
        sum = sum.subtract(new BigInteger(sb.toString()));
        return sum.toString();
    }
}
